The invention relates to novel application of atipamezole hydrochloride, in particular to application of atipamezole hydrochloride as a non-specific P450 enzyme inhibitor. The atipamezole hydrochloride has no significant differences in the ability to inhibit various isozymes, the ability to inhibit CYP2C9 is particularly greater than 1-ABT, and small species differences are caused. The veterinarydrug atipamezole hydrochloride is used as a new-generation P450 enzyme non-specific inhibitor and is suitable for in-vitro and in-vivo researches on animal, and is also applicable to in-vitro body systematic research; as the inhibitory action of the atipamezole hydrochloride is original but not metabolic, pre-hatching is not required when the atipamezole hydrochloride is used to perform in-vitro research, and administering in advance is not required in in-vivo research; the atipamezole hydrochloride has the significant advantage of replacing existing classic tool drugs 1-ABT.